Invisible Porous Ink

A very fast drying invisible ink for porous substrates, which can be applied by pen or spray. It is designed to fluoresce blue at 380nm under ultraviolet light. Very fast dry time, variations in temperature and humidity may affect dry time. Application best used in a pen or spray on porous substrates. Solvent based chemical, and dye based colorant. Use within 1 year is recommended. Ink should be stored at normal room temperature and capped tightly after each use. Available in pints, quarts and gallons.